<script lang="ts" setup name="GoodsImage">
import { computed, ref } from 'vue';
import { useMouseInElement } from '@vueuse/core'
defineProps<{
  images: string[]
}>()

// 定义一个默认的高亮下标
const active = ref(0)
const target = ref(null)
const { elementX, elementY, isOutside } = useMouseInElement(target)

// 获取鼠标的位置信息
const position = computed(() => {
  let x = elementX.value - 100
  let y = elementY.value - 100
  // 边界处理
  if (x <= 0) x = 0
  if (y <= 0) y = 0
  if (x >= 200) x = 200
  if (y >= 200) y = 200

  return {
    x,
    y
  }
})

</script>
<template>
  <div class="goods-image">
    <!-- 右侧的盒子 -->
    <div  class="large"
          v-show="!isOutside"
          :style="[{
                      backgroundImage:`url(${images[active]})`,
                      backgroundPosition: `${-position.x * 2 }px ${-position.y * 2}px`
                   }
                  ]"
      >
    </div>
    <!-- 用户hover的区域 -->
    <div class="middle" ref="target">
      <!-- 
        isOutside: 判断鼠标是否在元素外
                   在元素外 - true
                   在元素内 - false

        在元素外, 移动的遮罩层和右侧的盒子都不显示 (取反)
       -->
      <!-- 移动的遮罩层 -->
      <div class="layer"
        v-show="!isOutside"
        :style="{ left: position.x + 'px', top: position.y + 'px' }"
        >
      </div>
      <img
        :src="images[active]"
        alt=""
      />
    </div>
    <ul class="small">
      <!-- :class="{ active: index === 1 }" -->
      <li
        v-for="(item, index) in images"
        :key="item"
        :class="{ active: active === index }"
        @mouseenter="active = index"
      >
        <img
          :src="item"
          alt=""
        />
      </li>
    </ul>
  </div>
</template>

<style scoped lang="less">
.goods-image {
  width: 480px;
  height: 400px;
  position: relative;
  display: flex;
  z-index: 500;
  // 右侧的盒子
  .large {
    position: absolute;
    top: 0;
    left: 412px;
    width: 400px;
    height: 400px;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
    background-repeat: no-repeat;
    background-size: 800px 800px;
    background-color: #f8f8f8;
  }

  // hover的区域
  .middle {
    width: 400px;
    height: 400px;
    background: #f5f5f5;
    position: relative;
    cursor: move;
    // 移动的遮罩层
    .layer {
      width: 200px;
      height: 200px;
      background: rgba(0,0,0,.2);
      left: 0;
      top: 0;
      position: absolute;
    }
  }
  .small {
    width: 80px;
    li {
      width: 68px;
      height: 68px;
      margin-left: 12px;
      margin-bottom: 15px;
      cursor: pointer;
      &:hover,
      &.active {
        border: 2px solid @xtxColor;
      }
    }
  }
}
</style>